Innovative Application of EL Defect Detector for Solar Modules

　　I、 Technical Principles and Development Background

　　The Electroluminescence Detection device for solar modules is a key quality inspection equipment in the field of photovoltaic manufacturing. It applies a forward bias to the solar modules to emit near-infrared light and captures defect features with a high-sensitivity camera. Compared to traditional manual inspection, the EL defect detector for solar modules can identify various process defects such as micro scale hidden cracks and broken gates, with a detection accuracy of up to 99.7%.

　　In recent years, with the popularization of new technologies such as double-sided modules and TOPCon, the EL defect detector for solar modules has been iterated to the fourth generation of intelligent models. The latest data shows that the global market size of solar panel EL defect detectors will exceed 2.8 billion yuan in 2024, with a compound annual growth rate of 19.3%, of which Chinese manufacturers account for 67% of the market share.

　　II、 Analysis of core functional modules

　　1. The optical imaging system solar module EL defect detector adopts a scientific grade CMOS sensor, combined with an 850nm bandpass filter, which can penetrate 3.2mm tempered glass to capture internal defects of the battery cell. The model is equipped with a 60 megapixel scanning array, which compresses the detection time of a single component to 12 seconds.

　　2. The intelligent analysis algorithm trains a defect recognition model through a deep learning framework, enabling the solar module EL defect detector to have adaptive discrimination capability. Tests have shown that the accuracy of identifying PID attenuation in PERC components has increased by 43% compared to traditional methods.

　　3. The cloud based quality traceability online solar module EL defect detector is equipped with MES system interface, and the detection data automatically generates QR code labels. The application shows that this function improves the efficiency of quality traceability by 300%.

　　III、 Typical application scenarios

　　1. The online inspection of the production line deploys a solar module EL defect detector after the component lamination process, which can monitor the stability of the welding process in real time. By optimizing the layout of the detection station, the fragment rate was reduced from 0.8% to 0.15%.

　　2. The portable EL defect detector for outdoor power station acceptance supports operation in an environment of -20 ℃~60 ℃. In 2024, a 300MW photovoltaic project discovered hidden defects in 7.2% of the components through mobile inspection.

　　3. In the development of TOPCon batteries, the solar module EL defect detector can quantitatively analyze the impact of POLO structure on hidden crack propagation, providing data support for process improvement.

　　IV、 Technological development trends

　　1. The new generation of EL defect detector for solar modules is integrating PL (photoluminescence) detection function through multimodal fusion detection, which improves the accuracy of defect classification through dual-mode data fusion.

　　2. The AI predictive maintenance based component life prediction model constructed from detection data can upgrade the solar module EL defect detector from a quality inspection tool to a reliability evaluation platform.

　　3. The standardization process is accelerating, and IEC 62941:2025 has for the first time included the EL defect detector for solar modules in the certification standard for photovoltaic modules, stipulating that the maximum defect area for B-class modules shall not exceed 3%.

　　With the continuous advancement of photovoltaic technology, the EL defect detector for solar modules is developing towards intelligence and integration. In the next five years, a new generation of devices combining quantum dot imaging and digital twin technology may redefine photovoltaic quality control standards.